227
Atoms are too small to see with microscopes that rely on light (also due to problems such as the Abbe diffraction limit). Essentially, with a conventional microscope you cannot distinguish points that are too close.
Even the recently introduced superresolution microscopes, which can surpass this limit, are still not able to image single atoms (they can, ...
145
The GIF was sourced from the International Space Station video by astronaut Don Pettit. The video depicts small water droplets orbiting a polyethylene knitting needle which was charged by rubbing it with a piece of paper. Don Petitt states that the blue knitting needles are "8mm in diameter".
In the video, Don Pettit clearly says that the attractions are ...
115
Genetic science in Mahabharata
Prime Minister Modi claimed that genetic science and plastic surgery existed in Ancient India.
source: “We all read about Karna in the Mahabharata. If we think a little more, we realise that the Mahabharata says Karna was not born from his mother’s womb. This means that genetic science was present at that time. That is ...
105
No. It is a complete invention of an urban myth.
Unless anybody produces a Royal Navy document that even does any mention of this influence of Coriolis effect, this seems to be just untrue. A complete fabrication for a good story – good for teaching physics but very bad history.
It seems to be an annoying urban myth. The Coriolis effect is present and ...
101
No discussion of atoms would be complete without mentioning Brownian motion.
Brownian motion is the strange, seemingly random movement of small particles (like dust) when suspended in a fluid. This phenomenon went unexplained for almost 80 years, until Einstein published a paper in 1905 (the same year he published his paper on the special theory of ...
answered Feb 2 '12 at 18:13
BlueRaja - Danny Pflughoeft
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92
No, it is not true
On the Wikipedia page on "Antistatic Device" there were several references to these kinds of things having been examined in a serious manner.
ESD Journal
It is our opinion that no currently available methods or devices exist which will effectively ground a person without a tethered cord to ground or at least a large capacitance.
...
84
Without acknowledging any of the conditions actually present in the church, wood fires can get much hotter than 600 °C.
The maximum temperatures measured within the pile were of the order of 800, 1000, and 1200 °C for piles composed of 1.27, 2.54, and 9.15 cm sticks respectively, although the maximum temperatures for a given size stick appeared, from ...
79
In the television show Penn and Teller Tell A Lie, a competitor to Mythbusters, they conduct an experiment to try this.
Here is a YouTube video of the result.
In the single instance they show with a slow motion camera, the bullet is indeed at split in half - or at least, fragmented into pieces - by a normal butter-knife. This is not a large sample, and ...
78
It's possible they are actually talking about the rate of energy given off by the Sun that reaches the Earth. However, they are not talking about the amount of energy released, but rather the rate of energy released.
The "laser at Magurele, Romania" is actually part of the Extreme Light Infrastructure, a pan-European research project, described by ...
74
TL;DR; The F-15 is somewhat unique among current airframes, in that its body shape and size induce a certain amount of lift. That extra lift, along with the speed achievable with afterburners, allowed this aircraft to recover from an incident which would bring down most other aircraft.
The fact that we have a picture of this aircraft on the ground and ...
66
Yes, GPS requires both general and special relativity to work
[Note this is simplified account based on this and this (MS word download)]
We can understand why by looking at how GPS actually determines where you are. The system relies on a number of satellites transmitting signals and your GPS device receiving those signals (see wikipedia). There are about ...
65
Mechanical Resonance
Certain types of bridge are susceptible to mechanical resonance effects even when marching soldiers are not involved.
Mechanical structures usually have one or more frequencies at which some part of the structure oscillates. A tuning fork has a well-defined natural frequency of oscillation. More complex structures may have a dominant ...
59
According to SamuraiSwords.com, there are two folding steps, in first traverse and longitudinal folding is repeated:
The difference between these two folding procedures lies on that the
small hammer is used to fold in transverse folding while the big
hammer is used in longitudinal folding. Generally, about 12-15 folings
are repeated.
In second (...
58
Yes atoms undoubtedly exist.
I also had the doubt a few years back - are they real-real or just abstractions? - until the following, interesting and very convincing peer-reviewed literature on the topic came out!
D.M. Eigler, E.K. Schweizer. Positioning single atoms with a scanning tunneling microscope. Nature 344, 524-526 (1990).
Here we report the use ...
55
The primary issue with the Port Chicago incident being due to a nuclear device is that it would require us completely rewrite the currently known history of the Manhattan Project [1][2]1 to include "The Gadget" not being the first nuclear device and that if one was created for Port Chicago that it predated The Gadget by almost a full year as the Trinity Test ...
54
There is Frankin's letter of Oct 1 1752 saying that the kite experiment was performed successfully in Philadelphia, which was read to and published in the Philosophical Transactions of the Royal Society a few months later.
There is also Joseph Priestly's The history and present state of electricity (written about 15 years later after discussions with ...
54
Probably yes: According to at least one expert, the temperature in the Notre Dame fire must have been extremely high, and probably exceeded 600°C.
Yesterday the Süddeutsche Zeitung, one of Germany's most reputable newspapers, published an interview with the director of the German Technisches Hilfswerk (the Federal Agency for Technical Relief) and former ...
54
In 1953, a paper looking at some of the factors involved in beer foam answered this question almost as an incidental aside.
Jackson, S. (1953). FACTORS AFFECTING BEER FOAM I. CARBON DIOXIDE EVOLUTION. Journal of the Institute of Brewing, 59(4), 317–322. doi:10.1002/j.2050-0416.1953.tb02723.x
The main experiments described monitoring the CO2 emissions of ...
53
From HubbleSite - Behind The Pictures:
The Meaning of Color
The colors in Hubble images, which are assigned for various reasons, aren't always what we'd see if we were able to visit the imaged objects in a spacecraft.
We often use color as a tool, whether it is to enhance an object's detail or to visualize what ordinarily could never be seen ...
53
It is indeed a fact, based on the documents released by the FOIA, that both FBI and OSS (the precursor to CIA - CIA didn't exist at that time) obtained papers from Nikola Tesla after his death in 1943.
Some of the released material show that the Department of Defense (DoD), among others, was interested in these papers because:
"SUBJECT: Papers recovered ...
53
Only when the snow is "wet", not if the snow is powdery.
As this January 1910 Watson Wagon advertisement says:
The popularity of the Watson continues to grow like a snowball rolling down hill on a wet day.
This can even happen naturally as explained in the US National Weather Service article Snow Rollers Observed Across
Central Illinois (Spring 2003) ...
52
TL;DR : No, even if one chooses to interpret the excerpt of the Qur'an as such, the maths don't hold up
I am going to base this answer on your second source, as the calculation there is reduced to the minimum which makes it a lot easier to show its flaws. This is an answer on the mathematical aspect of the problem, not covering the interpretation of the ...
51
A lot of people hear that glass is a liquid when they hear about this particular misconception. Actually it is probably better to describe glass as an amorphous solid. Any variation in thickness comes strictly from manufacturing processes.
Molten glass is gathered on a blowpipe, and blown to an elongated balloon shape . The ends are cut off and the ...
51
Cecil Adams at the Straight Dope tested it with a small experiment, and then cited Thomas Peterson and Trevor Wallis of the National Climatic Data Center, who also did an experiment:
"One rainy day the two men donned identical sweat suits and hats, which they'd weighed before the test. For added accuracy, they wore plastic garbage bags underneath the ...
47
This is not a lightning strike. It's an underwater blasting explosion
Snopes covered this a few days ago. Here's the article. The video was originally posted to YouTube in 2012 to host it for this website.
The site says:
KÄÄNNY VEDENALAISESSA LOUHINTA- JA RÄJÄYTYSTYÖSSÄ AINA ASIANTUNTIJAN
PUOLEEN
Rantojen ja vedenalaisen kallion louhinta- ja ...
42
The technology he demonstrates for welding is well known and understood (see this patent from 1962), and is generally called an oxyhydrogen electrolytic torch or water torch. Water is decomposed into Oxygen and Hydrogen on demand. This has some benefits in difficult environments (e.g. underwater) and others where you wouldn't want to have cylinders of ...
41
The oldest confirmed use of any version of this quote that I was able to find is from Ray Cummings' short story The Time Professor, published in the Jan. 8, 1921 issue of Argosy All-Story Weekly (thanks to mgkrebbs for pointing this one out):
"I do know what time is," Tubby declared. He paused. "Time," he added slowly -- "time is what keeps everything ...
40
It's not just your culture. Advice from the US National Weather Service includes:
Stay away from windows and doors, and stay off porches.
The answer to this related question (including the transcript of interview with meteorologist John Jensenius) and this advice from National Geographic gives some reasons for the advice.
Metal frame windows and doors ...
38
Power of the laser
This video shows interviews with people at the laser center. At 4:54 you can see the director of the center repeat the claim. In this video, that same director states that the laser was measured at 10.88 PW or 1.088×10^16 W. Remember that watts (W) are the unit of power.
The laser does not operate at that power continuously. Just for ...
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